unexpected response when entering number into second positon

[zlbSwen]

Here is my props given to OtpInputs:
<OtpInputs
ref={ref=>this.optRef=ref}
......
numberOfInputs={6}
caretHidden={true}
selectTextOnFocus={false}
/>
First, input three numbers, then press backspace until only one number(the first one) left.
Then, type in one more number, causing the keybord dismissing and unable to input more, it just stuck.

When I change selectTextOnFocus={false} to true, it works fine. But I don't want user to select the text.